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arXiv · 1001.3773

Comparative study of theoretical methods for nonequilibrium quantum transport

J. Eckel·F. Heidrich-Meisner·S. G. Jakobs·M. Thorwart·M. Pletyukhov·R. Egger
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Abstract

We present a detailed comparison of three different methods designed to tackle nonequilibrium quantum transport, namely the functional renormalization group (fRG), the time-dependent density matrix renormalization group (tDMRG), and the iterative summation of real-time path integrals (ISPI). For the nonequilibrium single-impurity Anderson model (including a Zeeman term at the impurity site), we demonstrate that the three methods are in quantitative agreement over a wide range of parameters at the particle-hole symmetric point as well as in the mixed-valence regime. We further compare these techniques with two quantum Monte Carlo approaches and the time-dependent numerical renormalization group method.

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J. Eckel, F. Heidrich-Meisner, S. G. Jakobs, M. Thorwart, M. Pletyukhov, R. Egger. 2010-05-01. Comparative study of theoretical methods for nonequilibrium quantum transport. https://doi.org/10.1088/1367-2630%2F12%2F4%2F043042

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